A semantic relationship knowledge base is a body of data that identifies relationships in meaning between pairs of words. These relationships are represented as a "semantic relation path." A semantic relation path is a sequence of one or more semantic relations, which each have a relation type that relates the meanings of two words. For example, such a knowledge base might include the following semantic relation paths between the words "boat" and "water": EQU boat-Purpose.fwdarw.travel-Location.fwdarw.water (1) EQU boat.rarw.TypicalSubject-float-Location.fwdarw.water (2)
Semantic relation path (1) contains two relations, "boat-Purpose.fwdarw.travel" and "travel-Location.fwdarw.water," and relates the meaning of "boat" and "water" by indicating that a boat has a purpose of traveling in water. Semantic relation path (2) similarly contains two relations, and relates the meaning of "boat" and "water" by indicating that a boat typically floats in water.
Many fields of endeavor can gainfully utilize a knowledge base that identifies the salient semantic relationships between pairs of words. For example, in natural language parsing, when a parser encounters a modifying phrase, it needs to identify the word or phrase that the modifying phrase modifies. This is also known as identifying the "attachment point" of the modifying phrase. For example, when parsing the sentence
We observed the bird with a telescope.
a parser must determine whether the modifying phrase with a telescope"modifies the verb "observe," or the noun "bird." This is tantamount to determining whether the semantic relation path (3) EQU observe-Means.fwdarw.telescope (3)
or similar less direct paths are more salient than either of the semantic relation paths (4) and (5) EQU bird.rarw.Possess-telescope (4)
or EQU bird-Part.fwdarw.telescope (5)
or similar less direct paths. Based on a determination that the degree of saliency of semantic relation path (3) exceeds the degree of saliency of semantic relation paths (4) and (5), the parser would conclude that the modifying phrase "with a telescope" modifies the verb "observe." An effective approach to automatically weighting the relative saliency of semantic relation paths would therefore have significant utility.